With the development of the network communication technique and the large-scale commercialization of the 3G technique, the user puts forward a higher requirement for high reliability and real time of the service, and at the meantime, the high reliability is the basic requirement of the carrier-class equipment and the basic starting point of the telecommunication operators. The standard organizations all provide solutions of the link quick switching/backup at the control plane for the 3G network control protocol, however, there is not a specific solution mentioned for the quick switching of the forwarding path (hereinafter referred as “the bearer link at the user plane”) between the external interface and the user plane.
The Iub interface of the network element system Radio Network Controller (RNC) is taken as an example. As shown in FIG. 1, the RNC comprises an ATM Adaptation Layer Type 2 (AAL2) signaling control protocol resident board, an active Iub interface board, a standby Iub interface board and a plurality of physical ports, wherein the AAL2 signaling control protocol resident board notifies the active Iub interface board and the standby Iub interface board to establish/delete/modify the bearer link, and the active Iub interface board and the standby Iub interface board support the active and standby switching function of the board.
At present, the high reliability of the Iub interface board is actively ensured by port protection or a backup between the active Iub interface board and the standby Iub interface board, wherein the port protection comprises protection implemented by internal ports and protection implemented between the external interfaces. However, the protection and backups are the protection only among the physical ports, physical links or boards, but there is not the protection performed for the bearer link at the user plane.
Actually, for the bearer link at the user plane, in the network element system RNC shown in FIG. 1, the AAL2 signaling control protocol resident board simultaneously sends the link establishment/deletion/modification message to the active Iub interface board and the standby Iub interface board, and the active Iub interface board and the standby Iub interface board will respectively establish/delete/modify the bearer link on the local board after receiving the link establishment/deletion/modification message, thereby being able to switch the data stream at the user plane on the active Iub interface board to the bearer link on the standby Iub interface board when the active and standby switching occurs in the active Iub interface board and the standby Iub interface board due to the causes such as the active Iub interface board failure or manual operations and so on.
However, due to the causes such as the continuous access and exit of the user, the restarting and replacement of the standby Iub interface board, the message loss and link operation failure of the AAL2 signaling control protocol resident board and so on, the inconformity of information on the active Iub interface board and the standby Iub interface board might be caused, for example: a link redundancy, a link deficiency or parameter incorrectness on the standby Iub interface board. Therefore, after switching the active Iub interface board and the standby Iub interface board, there may occur problems that: (1) the user is off-line on account of the inconformity of the bearer links on the active Iub interface board and the standby Iub interface board; (2) the replacement and upgrade of the active Iub interface board and the standby Iub interface board are unable to be supported and so on.
Due to the existence of the above problems, the user plane processing cannot perform the traffic control exactly after the standby Iub interface board becoming as the active Iub interface board, which will reduce the access capability or result in a traffic burst, thereby data at the user plane born on the interface board being unable to be forwarded correctly and the service of the on-line user can not be ensured.